Much of the riddle of reinsurance can be answered by answering the question "What are the reasons why reinsurance is purchased?" For some ceding companies and their reinsurers, an important result of a transaction is the existence (or the perception) of risk transfer, for financial as well as risk management reasons. This panel will discuss various ways risk transfer can be evaluated and other elusive quantitative tasks of reinsurance reserving, such as reserving for excess of aggregate covers. Some prior knowledge of reinsurance is presumed for this session.